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(No Mqdel.) 3 Sheets-Sh-eet 1.

E. FIELD. APPARATUS FOR PRODUCING MIXTURES 0F STEAM AND HOT AIR. No.479,707. Patented July 26, 1892 V E. FIELD.

(N0 M0 e1.)

IXTURBS OF STEAM AND HOT AIR.

- Patented July 26, 1892.

US FDR PRODUCING M No. 479,707.

llllll (no Model.) 3 Shets'QSheet 3.

E. FIELD.

APPARATUS FOR PRODUCING MIXTURES 0F STEAM AND HOT AIR.

Patented July 26, 1892.

i, mum?! a fwvenifor' w e W UNITED STATES PATENT OFFICE.

EDIVARD FIELD, OF LONDON, ENGLAND.

APPARATUS FOR PRODUCING MIXTURES OF STEAM AND HOT AIR.

SPECIFICATION forming part of Letters Patent No. 479,707, dated July 26,1892.

Application filed March 10, 1891- Serial No. 384,509. (No model.)Patented in England March 21, 1890, No. 4,432; in France January 26,1891, No. 210,992; in Belgium January 26, 1891, No. 93,552: in NorwayI'ebrnary17, 1891, 110.2,174; in Switzerland February 17, 189L110.3,453; in Germany February 18, 1891, No. 63,680; in Lnxemburg February18, 1891, No.1,410; in Victoria March 25,1891,N-8.615; in SouthAustralia March 26, 1891, No. 1,896; in Italy March 31. 1891, LVII, 366;in Queensland March 31, 1891, No.1,295; in New South Wales March 31,1891, No. 2,894; in New Zealand Aprilll, 1891, No.4,933; in BrazilApril15,1891, 110.1,152; in Spain April 24, 1891, N0.11,7941 inAustria-Hungary June 17, 1891, No. 9,256, and in India October 5,1891,N0. 90.

.To all whom it may concern.-

Be it known that I, EDWARD FIELD, a subject of the Queen of GreatBritain and Ireland, residing at Buckingham Street, in the city ofLondon, England, have invented Apparatus for Producing the Mixture ofSteam and Hot Air for Use as Motive Fluid in Engines, (for which I haveobtained Letters Patent in Great Britain, No. 4,432, dated March 1o 21,1890; in France, No. 210,992, dated January 26, 1891; in Belgium, No.93,552, dated January 26, 1891; in Austria-Hungary, No. 9,256, datedJune 17, 1891; in Germany, No. 63,680, dated February 18,1891; in Spain,No. :5 11,794, dated April 24, 1891; in Norway, No.

2,174, dated February 17, 1891; in Switzerland, (provisional,) N 0.3,453, dated February 17, 1891; in Luxemburg, No. 1,410, dated February18, 1891 in Italy, Reg. Att., Vol. LVII, No. 366, dated March 31, 1891;in Victoria,

No. 8,615, dated March 25, 1891; in Queensland, No. 1,295,dated March31, 1891; in New South Wales, No. 2,894, dated March 31, 1891; in SouthAustralia, No. 1,896, dated March 26, 1891; in New Zealand, No. 4,933,dated April 11, 1891; in Brazil, No. 1,152, dated April 15, 1891, and inIndia, No. 90, dated October 5, 1891,) of which the following is aspecification.

This invention has reference to apparatus for producing mixture of steamand hot air for use as motive fluid in engines, according to theinvention described in the specification of another application forLetters Patent filed by me at the time of filing the presentapplication, and serially numbered 384,508. In carrying out thatinvention air is mixed with steam as follows: The air (which it isdesirable should be free from any excess of moisture) is compressed to apressure equal,

or thereabout, to the intended working pressure of the motive finid'inthe engine. Then the air thus compressed is passed alone through anysuitable form of heater placed in the fine or fines of a boiler or inanyother convenient position where it will receive suflicient heat fromany source to raise the air under pressure passing through the heater toa temperature of, say, from 400 to 500 Fahrenheit, or thereabout, thuscausing considerable increase in the volume or pressure of the air.Steam is supplied from a boiler or generator, and it and the compressedair are conducted simultaneously but separately through wellprotectedmains to a mixing apparatus, hereinafter called a mixer, in which theyare mixed. The steam is by preference supplied at a somewhat greaterpressure than the compressed air. The mixture is conveyed from the mixerto the slide or valve jacket or casing of the motor in which it is to dowork.

In the accompanying illustrative drawings, Figure 1 illustrates, partlyin elevation and partly in vertical section, apparatus according to thisinvention for producing mixture of steam and hot air in the manner setforth, this apparatus being shown applied to a motivepower-engine. Fig.2 is a vertical section, to a larger scale, of an automatic steam andair mixer. Figs. 3 to 7, inclusive, are sectional views illustratingmodified constructions of mixers, hereinafter more particularlydescribed.

Referring to Fig. 1 of the drawings, 1 is a motive-power engine. It isshown as of a well-known horizontal single-cylinder type; but variousother types might be used whether, simple or compound. Usually it willbe advantageous to adopt the compound type. Itis also desirable that thecylinder or cylinders and slide or valve jacket or jackets should besteam-jacketed. The Water from such steam-jackets may be returned to theboiler in any known or suitable manner.

2 is a steam-boiler. It is represented as of the ordinary Cornish type,but might be of almost any other kind.

3 is an air-compressor.

It should be of good construction, capable of compressing atmosphericair to the working pressure required by the motor. As represented thiscompressor is arranged to be driven directly; but in many cases it willbe better to drive the compressor by a separate crank, so that itsaction may be correctly timed. Assuming the working pressure to be sixtypounds per square inch, the capacity of the compressor may be the sameas that of the motor-cylinder. In some cases the compressor may be madeof a variable capacity, or it may be caused to make a larger or asmaller number of strokes within agiven time than the engine, as may befound convenient.

4 isaheaterha'ving sufficient surface exposed to the action of the hotproducts of combustion to raise air forced through it to a suitabletemperaturesay from 400 to 500 Fahrenheit, or thereabout. The heater maybe of any suitable construction and may be heated from any convenientsource. In Fig. 1 it is shown as placed in the smoke-box of the boiler,so as to be heated by the hot gases and products of combustion passingfrom the boilerfurnace to the chimney.

5 is a pipe for conveying the compressed air from the compressor to theheater.

6 is a well-protected pipe for conveying the heated compressed air fromthe heater to the mixer.

7 is a mixer of suitable construction, as hereinafter more particularlyexplained with reference to the several examples illustrated.

8 is the steam-main.

9 is the steam-admission valve to the mixer.

10 is the starting-valve for the motor.

11 is a steam-shut-off valve.

12 is a well -protected mixture-main for mixed compressed hot air andsteam.

13 is the slide-jacket of the motor.

14 is a mixture-regulating throttle actuated. by governor.

The form of mixer I prefer to use is shown to a larger scale at Fig. 2.It is constructed with differential self-acting valves, the arrangementbeing such that when the valve controlling the ingress of the heated air(hereinafter called the hot-air valve) is opened by the pressure of thehot air the valve controlling the ingress of steam (hereinafter calledthe steam-valve will also be open ed, and when the hot-air valve isclosed by the conjoint pressure of the mixture of steam and hot air onthe hot-air valve and of the steam acting on the steam-valve thesteam-valve will also be closed.

15 is the steam-valve, having an area of one.

16 is the hotair valve, having an area of, say, eight, or thereabout;but the difference will vary according to the difference between theaverage pressures at which it may be intended to work. The valve 15 maybe made in one piece with the stem 17 and continued down to the bottomof a socket forming a step in the upper side of the valve 16, in whichit is loosely keyed, the valve 16 having a slight amount of play, sothat it may readily find its seat, care being taken that when bothvalves are seated the spindle shall be in contact with the step in valve16'at the point 18.

19 is the seat of the steam-valve.

20 is the seat of the hot-air valve.

21 is the steam-nozzle; 22, the hot-air passage; 23, the mixture-conduitto the engine; 2f, the condensed-water pipe; 25, the steaminlet from theboiler; 26, the hot-airinlet from the heater.

The method of working is as followsi The engine is started with steamonly by opening the valves 10 and 11, the mixture-main 12 and valve 9being open. After a'few revolutions the compressor will have forcedsufficient air through the heater to raise the pressure of the air up tothat of the-steam. The hot-air valve 16, Fig. 2, will then be lifted bythe excess of air-pressure. Consequently the steamvaive 15, Fig. 2, willlikewise be opened. Hot air and steam will then rush simultaneouslythrough the mixer, forming a volume of mixture considerably greater inbulk than the mere aggregate of the volumes of the steam and hot air,but at a pressure equal to the mean pressure of the steam and hot air.The result of this will be that the engine will run faster, for if thevolume of mixture be not used by the engine an increased pressure ofmixture will be the result. The direct steam communication from theboiler to the engine will then be closed by the shutting of the valve 10and the engine will continue running at its proper normal speed, thesteamsupply to the mixer being regulated by a governor or by any othersuitable means at 9 or 14; or the mixture may be regulated by a valve at14. Thus, as will be readily understood, the valve arrangement abovedescribed is entirely self-acting, closing when full pressure has beenattained in the slide-jacket and opening immediately on any reduction ofpressure taking place in the slide-jacket of the engine. When themixture in the mixturemain has attained approximately the same pressureas that of the compressed hot air in the hot-air main, the compoundvalve will be in equilibrium and both steam and hot-air valves will beclosed by the weight of the valves and stem, and will remain so untilthe pressure is reduced in the mixture-main by the demand of the engine,when the hot-air valve will be relieved of some of the pressure on itsupper side. To reduce the speed of the engine, it is only necessary tothrottle the steam passing to the mixer at 9. The construction andoperation of the mixer may be variously modified. Thus, instead of thesteampassing as a jet through the central passage or nozzle 21 and thecompressed and heated air through the surrounding annular passage 22,the construction might obviously be so modified that the steam might gothrough the annular passage and the compressed and heated air as a jetthrough the central passage or nozzle; but I prefer the arrangementshown. In either case, as will be understood, the ob- IIO ject is tokeep the hot gases of the air under pressure dry and separate from thesteam until after the passage of the point of mixture.

Fig. 3 represents the upper part of a mixer resembling that shown inFig. 2, but adapted to be mechanically moved. For this purpose 3" is aprolongation of the valve-stem, which extends through a stuifing-box 19and by a link 20 is connected to a suitably-operated bell-crank 21 Fig.4 illustrates a modification wherein slide-valves 15 16, mechanicallymoved, are used in lieu of the self-actinglift-valves illustrated inFig. 2. The valve-rods 3 3 extend through stuiiing-boxes 19 19 and areconnected to suitable actuating means 21.

Fig. 5 shows a self-acting lift-valve mixer similar to that shown inFig. 2, but Without the steam-nozzle 21.

Fig. 6 shows the same adapted to be mechanically moved by the samearrangement as described with reference to Fig. 3.

I am aware that it has heretofore been proposed to employ in conjunctionwith a steamsupply pipe an air-compressor and air-heater for supplyingheated compressed air for producing a mixture of steam and hot air; butin such apparatus the steam and hotair valves have been opened andclosed separately and in succession, so that the mixture was produced byadmitting heated compressed air into a valve chest previously chargedwith steam. I therefore do not claim such apparatus, broadly; but

What I claim is r 1. Apparatus forproducing mixture of steam and hot airfor use as motive fluid, comprising air compressing and heatingapparatus, steam-su pply apparatus, and a mixing apparatus having ahot-air valve and a steam-valve arranged to open and close together andsimultaneously controlling the admission of heated compressed air andsteam through separate inlets, substantially as described.

2. Apparatusforproducing mixture of steam and hot air for use as motivefluid, consistin g of air compressing and heating apparatus,steam-supply apparatus, and mixing apparatus comprising a vessel havingseparate inlets of unequal area for steam and hot air, a common outletfor mixed steam and air, a steam-valve, and a hot-air valve, said valvesbeing connected together and arranged to open and close together andsimultaneously control the passage of hot air and steam through saidinlets, substantially as herein described. v

3. In apparatus for producing mixture of steam and hot air for use asmotive fluid, the combination of air compressing and heating apparatus,steam-supply apparatus, and mixing apparatus connected with said air andsteam apparatus, said mixing apparatus having separate inlets for steamand hot air, a common outlet for mixed steam and air, and steam andhot-air valves of unequal area for controlling said inlets, said valvesbeing connected by a vertically-movable stem, whereby both valves willopen and close together, substantially as described.

4. The combination, with a fluid-pressure engine, of air compressingand'heatin'gapparatus, steam-supply apparatus, a mixer having separateinlets connected to said air and steam apparatus, respectively, and acommon outlet for mixed steam and air, a steamvalve, and a hot-airvalve, said valves being connected together and arranged to open andclose together and simultaneously control said inlets, and amixture-mainconnecting the outlet of said mixer with said engine,substantially as described.

5. In apparatus forproducing mixture of steam andhot air for, useinengines, the combination, with air compressing and heating apparatus andsteam-supply apparatus, of a mixer provided with differentialself-acting valves for admitting steam and hot air simultaneously butseparately thereto and a mixture-main into which mixture of heatedcompressed air and steam is delivered from said mixer.

6. The combination, with a fluid-pressure engine, of air compressing andheating apparatus, steam-supply apparatus, a mixer provided withdifferential self-acting valves capable of automatically controlling thesupply of air and steam from said apparatus, and a mixture-main incommunication with said mixer and with said engine.

7. The combination, with a fluid-pressure engine, of air compressing andheating apparatus, steam-supply apparatus, and a mixer provided withdifferential self-acting 'valves capable of automatically controllingthe admission thereto of steam and heated compressed air from saidapparatus, a steam-nozzle, and a hot-air passage, for the purposespecified.

8. Forproducing mixture of steamandhot air for use in fluid-pressureengines, a mixer having inlets for steam and heated com,- pressed air,an outlet for mixture of heated compressed air and steam, anddifferential self-acting valves of unequal area for simultaneouslycontrolling said inlets for steam and heated compressed air.

9. For producing mixture of steam and hot air for use in fluid-pressureengines, a mixer havinginlets 25 and 26 for steam and heated compressedair, respectively, a steam liftvalve 15 and a hot-air lift-valve 16, forsimultaneously controlling said inlets, said valves being of unequalareas, a stem 17, connected to said steam-valve and loosely connected tosaid hot-air valve, a steam-nozzle 21 in communication with saidsteam-inlet, and a hot-air passage 25, surrounding said steam-nozzle,substantially as herein described, for the purpose specified.

10. The combination of an engine, a steamgenerator 2, an air-compressorand means for driving the same, an air-heater in communi- I In testimonywhereof I have signed my cation with said compressor, a mixer 7, a pipename to this specification in the presence of 8, with valve 9, forconnectingsaid mixer two subscribing witnesses.

- with said steam-generator, a pipe 6, connect- EDWARD FIELD. 5 ing saidmixer with said air-heater, a mixture- Witnesses:

main 12, with valves 14, for connecting said ARTHUR WOOSNAM, mixer withsaid engine, and a pipe 8, with YorkHouse, South End, Essex.starting-valve 10, for connecting said engine WVM. THOS. MARSHALL,

direct with said steamgenerator, substan- Gentm, 2 Popes Head Alley,Oornhill, Lonro tially as herein described. don.

